1. Field of the Invention
This invention pertains to a fluid filter having structure for draining used fluid and for cleaning a renewable permanent filter media, and to a filter having an improved bypass valve that will bypass fluid at a pre-determined pressure drop; the filter will operate effectively without changing spring tension, in all pressure systems from 20 to 100 p.s.i.
2. The Prior Art
It is a known fact that the more often the engine oil is changed, the longer the vehicle engine will last. It is also well-known that a clean filter is important to the life of the engine. Most people do not take advantage of these well-known facts. Oil and filter changing is a dirty and undesirable task. It has become a franchised business in the United States to offer a "quickie" oil and filter change. The practice of routine oil and filter change extends the life of a vehicle engine; a worn engine wastes fuel and emits excessive noxious fumes. As previously mentioned, the oil and filter change is a popular franchised business. Service stations as well as car dealers specialize in oil and filter changes. However, each year there is less service performed by them and many have closed these facilities and have gone to self-service operations or have closed indefinitely, leaving fewer places where this task can be done for the car owner. This creates an inconvenience and effects a more expensive cost of maintaining the proper oil and filter change intervals. Consequently, the disadvantages of having it done are leading the car owner to do-it-yourself methods which are dirty and dangerous where the do-it-yourselfer has to raise the car and get beneath to open the oil drain and also remove the filter, resulting in a dirty mess, not to mention time consumed. In spite of this, do-it-yourself oil and filter changing has become very popular. Both oil and filters can now be purchased very economically at discount stores, auto accessory stores and even in drug stores. Nevertheless, it leaves the car owner with the dirty, unpleasant task of cleaning oil and filter.
Many more people would turn to the do-it-yourself way if it were to be made easier and less of a mess.
The most revelant known prior U.S. patents are Nos. 2,068,727 and 3,282,380. The former teaches use of the oil pump in an idling engine to evacuate the engine sump of used oil via a hose into an oil bucket. The latter device has a separate battery operated pump to evacuate an engine sump. Neither of these examples have any teachings or suggestion of flushing a renewable filter during evacuation.